Method of manufacturing concrete blocks for building purposes.



PTBNTUD APN. 9, 1907.

NolV 850,112.

.. l SLW'. HBNUIII-CKSON. METHOD OP MANUFACTURING CONCRETE BLOCKS POR BUILDING PURPOSES I Esas..

APPLICATION FILED PEB. 13, 1907.

'Inventor Vi/tnesses; i

lknown chemical action to constitute a manent unit. The manufacture. shoul be, `conducted where these materials can be UNITED sTATns* PATENT OFFICE;

SIDNEY W. HENDRIoKsoN, or VWHITE PLAINS, Naw vonk. METHOD lof YMANuF/iciumm; CONCRETE BLOCKS Fon nulLDiNG PURPOSES.

Specification of Letters Patenti..

atented April 9, 1907.

Original applioationhiiled April 21, 1906, Serial No. 312,941. Diviiiodand this application iledfebruary 13,1907. Serial $15,357,159.

To all whom, it may concern,.-

Be it known that I, SIDNEY W. HENDRICK- SON, a citizen of thcUnited States, residing in White Plains, in the county of Westchester and State of New York, have invented a certam new and useful Improvement in the Method'of, Manufacturing Concrete Blocks for Building Purposes, of which the following is a specification.

I operate mainly l ment and. sand and stoneunited y the longeasily brought :by chea transportation. The work can be performe `by unskilled labor at any ordinaryltemperatures.

My invention avoids some ofthe serious difficulties in rapidly and economically pro clucing by cheap andreliable means known as the wet process blocks having fine surfaces and strong and cheaply-made central portions, with a very e'ihcient arrest of heat, moisture, and sound. 'I will describe. it as applied to the production of two-faced building-blocks of an ordinary convenient size, cored, usingthe term concrete to .include all rades of c'oarseness of sand or gravel. .I wil? use the term half-dry to-meana condition of the powder havingaboutoneuarter as muchwater as itwill hold and wi use.

the term4 dry or dry powder when nc'cess'ary to designate the proper mixture of cement with sand before the water has beenA added to it. I 'can by my inventionproduce a hollow concrete block molded wet, using. a mixture' of .cement and sand and of stone up to .sevl

eral inches in diameter and remove 'the block from the mold without necessarily waiting any time for the material to set. v Y

I. have discovered that it is practicable to so introduce stones, more especially broken and therefore rough and angular stones, into the mold as to not onliyl1 economize the plastic' material, but also to old. it in shape durin itsl early stages, so that so soon as the bloc is completely rammed and its upper surface struck off the mold may be taken apart and the blocks being successively carried away, each on a proper pallet, and ranged in a proper slow-drying'place. The? mold may after each operation le".immediately a d j usted and the production ofv the 'succeeding block commenced. I havealso discovered that a thin mortar--grouthin percolating through a facing layer of fine granular material from the interior outward leaves niost of its cement on the-Way and arrives at the outer surface of the block 'nearly orquite reduced to the .condition of water, and` also that the tendency to l the formation of bubbles and of cavities produced thereby in the'surface of concrete cast wet may be avoided hyp-applying an exterior layerA with an excess o fv Water and applying dry or relatively dry material on-what is tov be inner face. Based. on these, I liave devised a methd of manufacture whiff i avoids .the

,usual gray color of the cement and allows us to have any .desired fineness and color in'one face or in more faces of a block cast wet from mainly gray material. The invention can be operated with but little expense for apparatus; Itrequireslittle skill, gives reat strength, and provides very erfect sur aces.

I have develo e my invention to provide a Widely-extened air-space-near the inner face, which avoidsthe transmission bothv of heat and moisture, and when the several tiers of my blocks are properly ap lied togather in building up a wall therewit taking care' to preserve and match these spaces, allows a free circulation of air in the wall, which contributes greatly, to" prevent the penetration of moisture to the interior of the building.

B f my invention either the front face or the )ack face, or both, may have the color of brownstone or other color, according to the material used in the iine facing, and the walls built with my blocks will be always dry and be warm in winter and cool in summer.

AThe following is a description Aof what I consider invention. p

The accompanying drawings form a part of this specification- Figure lis a plan view of the parts 'whichl constitute the upright sides and ends, ofthe mold and showing a'pallet in position. Fig. 2 is a cross-section of the removable liask or casing' and of the bottom board or pallet. It is on thcline 2 2 in Fig, 1, Fig. 3 is a section correspondinl to I1`ig..2 after the mold has been incliner and the material for the upf vright front layer has been molded-.in place andthe cores inserted. Fig. 4 -s a section after the mold has been restored to its level good meansofcarrying out thev ioo position and the previously-.molded back plates have been set in the proper u right position in. the mold, 'Flg. 5'is on a erger scale. It '1s a cross-section illustrating the plates.

larger scale. Figs. .6,`7, and 8 are all sec' tions on the line 2-2 on the same scale as Figs. 1, 2, 3, and 4. [They show later successive stagesI of manufacture of the final block. Fig. 6 shows the iirst and main Awith the inner.` faces coated with zinc and instalment of the shows the conditionV after the large stones .have been dropped in.

\ of the block on the line 9 grout introduced. Fig. V7

Fig. 8 shows the condition after the' half-dry has been ap plied and' rammed. Fig. 9 is a cross-section is completed, supported by the pallet alone.

Similar letters of reference indicate' like parts in all. the figures where they appear.

A is a mold having its sides and ends flexibly and separably connectedin any convenient manner to s' ape and liberate a molded block. Itissupported soas to allow it to be partially revolved or'tilted. Whlch is to mold the'outer face-of the block, by which'I mean the face -which is presented to the eye on the exterior ol the'building, is carefully wrought to produce the required plane surface or any desired pebbling,panel-' ing, or floral or other decoration. y

Itimay not be necessary to give a minute description of the mold, maybe cast-iron, preferably for some Work burnished. Only one mold andone setof cores are required, with a good supply of lane bottom plates, sometimes termed pallhts, (eachl of the latter with the usual aper* Y tureslfor the cores,) to do a large business.

' One of the materials required vis stone H of any strong and enduring uality suitable for building and 'small enoug to apply in the mold A after the-cores O have been raised into their places so as to occupy their ordij nary positions' in the interior. Refuse from other stonework is preferable; but ordinary boulders may serve .well -for a part of the stone skeleton. l

ular shapes, for the reason that they give more extended and rougher surfacesfor the adhesion of the cement and sand and also for the reason already intimated that-I depend Vupon' the property--of the natural stones introduced to4 stand in a manner akin to their lstanding in a stone Wall or pier to aid the slight holding force ofthe plastic material in keepin all the parts of my artiiicia -stone block ly in position relatively `to .each other Whenthemoldis irstremoved Another material required is-cement, .preff erabl some of the grades of Portland cement. Another'material issand', either natural or produced b crushing. There should be two is, one being 'common lsandfor` grades oft the interior or body of the block and the other, J havinthe color required'to showin the front of the uilding. In a large business 9 in Fig.` 1 after it' designate as headed rivets.

One side A,.

All the parts thereofA I-give a preference to irreglzontal amount of cement there may beurther subdivisions; but convSider the plant fairly com lete forgood and block. The double plates thusformed must be prepared in advance and become partially set, so as to have the strength. required -for gentle handling before'the manufacture of the remainder of the block.' In preparing I procure. a sufficient quan# tity of small tie-pieces of low steel or other metal D enlarged'at each end, whichI' will I provide a mold ofthe required size and a suilicicnt Istock of removable plane bottoms allets.

Placing this shallow preliminary mo d ina level position, I pour 1n and evenlyl s reada wet mixture of sand of any desired co or and cement for the double plate, making a uni form layer E of a half-inch or more in depth.

Next I sift a little dry cementv on theupper surface, which has the effect to remove all airbubbles from that portion of the concrete, an d by hand o r otherwise then insert the double-- headed rivets or tie-pieces D, leaving the up#` 'per ends projecting` Next I .ift a layer of sawdust and sand on .the concrete, forming-a layer K a half-inch, more or less, in dep th, and lastly I apply gently upon the Wet saw `lust and sand enoi'ighadditional sand and cement tomake a third layer of'about equal thickness or-alittle less, 'and after the materialfor bothtle-layers E and F properly, held apart Vby the wet sawdust and sand K has been moderatelycompressed the body f this prelimnary mold is lifted away to be used with After being-al-A other bottoms or pallets. lowed 'to lie twenty-four to `forty-.eight hours, resting on the bottom'of the mold-fin a horiposition, the duplex plate maj? be de rod.

tached therefrom, andeither'with orwithou-t l being allowed to stand on edge for a time is readyto beused.' Now tomake the main .block I use a quan-r tity of facing sand and mix the proper .therewith -to produce goodl concrete J. The proportion.may be two parts 'of finely-crushed stone or facingsand to'one of cement. y Imix in another bin convenientlyaceess'ible a goed stock of thin isemluid mortar, sometimes termedVs-lop or ^groi-1t,"viising therein sand containin a liberal proportion of small stones. I- ta e care inthis kousestr'ong lmaterial withoutv regard to color.

1 turche meid A with as from face A'- downw'ard at a'considerable angle, (see Fig.A

3,) and sift in a thin layerof halfdry powder, using the term half-dry to distinguish it l Y i ltann'ning is an important agency in com- "nearly corresponding ewa-.12'

previously dampened to about. the extent iioeessui' v to cohere when' compressed by hand. .ll' it is not cou'wnient to sift it, tho labor, always rather severe, may be varied b vsiniplysh'oveling. l'lowever introduced, .l use the hands with some suitable. iiu'plenient to pack it fairly andl tightly into all the intriczicies ol'v the'fi'ont laeeof the mold. .The

front :layer J thus` formed will be a little thicker at. thev edge which is to be 1at the bottom than at the top. It must, though technically dry, have when properly 4conipressed sul liv-lent strength to stand when the mold is turned, bringing .the pallet B level and the .front face A of the mold, and eolisequently the front .layer J ofthe block, upright. .'.lhe latter now st-ands in the position which .it is to hold in the: building. At this stage liline the other' portions of thomold with paper to avoid adhesion.. Next-1introduce in an upright position at the rear the double plate' VEV F', united by the ties l) above described, and we are ready tocom- 'mence the treatment which Will build'upthe interior of the body and also-supply'tlie moisture-under the right ciinditions forhar- (lening and perfeotingfthe frontA Withoutl hanging theeolor.

paoting the' main. b ody, and e'llicient rammel-s weighing 4in my experimental work about eight pounds 'are liberally used. .I lirst shove-liuto the. space around and between the cores enough thin -grout G to iill the mold A soi'netl'iing like quarter fulland followthis Wit-hstones ll, the latter dropped in and deture.

pressed, so' asv to f avoid i archesf or -unlfilled spaces. mixed powder, cheap sand l, and ram upon and into the mass, using little careexeept to ram fairly hard upon and bet'yveenthe stones, which shifts A them more or less in various directions;

but I' take care not to force any stone throu li the upright front layer, so as to appear on t e outer surface. The operation of applying grout and stones and ramn'iing isv repeated. This is an interesting stage of the manufac- 'lhe face side has beenbuilt up quite to the top with the faceJ of line and'carefnlly* placedl material of the desired color, and thc )ack side also standing to thefull height, with the thiuair-space e strongly brace by its 'lilling of clearrs'and and-sawdust and also by the '.doubleh-eaded ties or rivets l'ietveen the spaced par-ts E and F. 'The remaining spaee. in the moldthe large space not occupied by the cores between the.

also been filled nearly `to .the top with the relatively large stones I andthe gi'out.' Some small natural stones are novvfapplied and sunk into the slight remaining space at the top, `a little and partiallyset, as'

-or skeleton in its interior.

Without cement discoloration. vduce a handsome Concrete block-.byawet Next 'I sl'iovel in a 'morewstifl'ly' half-dry, made --with the4 the mold about front layer and,

the.uppersurl'ace .is struck. oil' level, and the molding process is Icomplete.

The distribution ol'tlie water isiinportant'. The 4excess .olwater in the groutgdis'appears as thework proceeds, par ily by being ab-I sorbed by 'the'l'ialf-dry-p'ow er and partly by its penetrating the right layers at the plates E' and li, spaced; a littlel .apart two parallel backA layers, having been previously wttedand partially set do. not absorb nuich'water; but the front la highly absorbent. The greater thickness of the lovser part 'of this front fac-e as' compared witlrthe upper'should be as nearly as praetieable just sullicient to balance the greater pressure and the longer time, which favors the penetrating of the water through this front layer at the bottom. The grout filters through to 'the face, and'when the mold is opened Athe completelymolded but as yet tender block of artificial stone stands properly on its supportingspallet withzall its faces exposed,'being able l pallet by the aid of the stones H, roughly piled and rammed so as t'o rest on each other and form a mass standing like axvall, column, .N oW the soaked paper is peeled oil/and4 the block-is'placed carefulll on a car and hauled away to the front and rear,

form' erJis.

to stand alone on the drying 4onse or shed, and immediately or soon after'it has -assgjned its fte in the tiers therein -the front face asI vbecome gently andiuniformly Wet all over' and sets I. thus prof process Inflle-of natural'stone and cement.

,lhe thinmaterial, as paper, forms an im- `portantfunction in preventing adhesion. It 1s useful in two Ways-first, by preventing theeontactfof the soft unsetmaterial with the inner facevof the mold, and, second, by facilitating the entrance of airinto the. joint when themold is opened, and thus reducingA the risk of distorting the soft mass. i

I can vary the manipulationby pouring one-third full of the Wet mix` ture, pressing it by forcing an iron plateof nearly the same-.size as the mold, haying grooves across the .upper surface, into the concrete mixture, removing the surplus water Which collects in the. grooves of the plate, and repeatii'ig this treatment till the mold is iilletl u The sawdust and sand between the parts E and F become loose with drying and can be removed by gravity by placing the-blocks so tha-titheextended air-spaces E will be held upright, aiding its discharge by blowing-or agitation, or both, if necessary .in any ease.

"M v theory of the action 1s that'in the act of filtering through tbe froiililayer J the'grput leavesr its denser portions 1in. the ,interiorl There must have been enough cement with- Ido out much water in the com' csitionof tlie upright front la er to 'set witli the Av'vaterwhieh it receives. 'attach im ortance to the fact that the face is hard an( weatherproof, and yet its exterior is not made appreciably gray by the access .of the grout, andthe face is more firmly bound to the body of the block,

because the strained cernentadheres across the entire interior.

Modifications maybe made Without departing from the `principle or sacrificing theA advantages ,of 'the invention. Obviously short lengths of wire, which may'be variously crooked and barbed can be introduced as a4 substitute for a ortion of thestones H. i

The filling aiu' ramming of the interior may be efl'ected at'one operation; butinyexperi-v ments indicate thatfi-t is preferable in most cases and with ordinary materials to eilicet.'

the filling at two "or three operations, as dcscribed. l have v-found 'two to giye VVery satisfactory results.

I do'not in this patent claim the Such' is n'iade the subject of aseparate application for patent', Serial No. 312,941.

I claim as iny invention The inethoddeseribed of-prmlucing artiicial building-blocks comprising the turning of ainold partially down upon its side, introducing cement and fine material of the desired -coler and forming thereof a front layer in the teniporarily-depressed side by theA dry process, a'lterwari-l 'rightingthe mold and ap}' l `ying-strong vand cheap materialthcreto for the body in a-too Wet condition, and al-` lowingr .the water to penetrate -therefrom tl'irough the 'fro-nt layer', all substantially as herein specified The method described of prod ucing arti iicial building-blocks comprising the turning of a mold partially down upon its side, intro-l d ucing cement and lii'ieniaterial of the desiredv color and forming thereof a front layer in the teiiiporarily-del'iressed side by the dryr process, afterward righting' the mold and 'forcibly ap )lying strongr and cheap material thereto inc iid-ing a pierdilie skeleton of natural stone, applying grcut at an early stage and compacting and .allowingr the excess of moisture in the body to penetrate the dry face and se( the latter without ail'ecting its color,n.li subsi ant iall y as herein specified.4

product.

3. The method described of producing artiicial building-blocks comprising the ccnstru ction of a frontlayer' of cement and ne mate rial of the desired color-introduced dry in a temporarily-depressed side of a mold,4 turning the mold upright and placing a previously-formed face on the opposite side forcibly applying strong and.v cheap material between such faces, including a nearly-solid skeleton of natural Stone, applying grout at an early stage and compacting and allowing the excess/of moisture in the lbody to penetrate l the dry face and set the latter Without aifecting its color, all substantially as herein speciy cial building-blocks com ris-ing the construction of a front layer o cement 'end ine material of the desired color introduced dry in a teinporarily-depressedl side of a mold, turning the mold upright and placingal preforcibly apply-nig strong and cheap material between such fac-es, including a nearlyfsolid skeleton of natural stone, introducing thin' 'yieldingmaterial as -paper to temporarily line the'other faces ofthe mold, applying- 8o grout and -compacting, and allowingr the excess of moisture in. the body topenetrate the dryfaceand set the latter Without affecting lits color, ,all substantially as herein specilicd.

dust, all substantially as herein specified.

Signed at New' York, N. Y., this' 18th. ,day of Jai'iunry, 1907.

SIDNEY YV. HENDRICKSON.

"Witiiesses:v I ,l

. Loris l?. BRAUN,

A. E. W. FRAZER. y

4. The method described of producing arti- ,yiously-formed face in 'the opposite side, 

